Black epoxy covering ICs?

[K1G1]

I've often noticed on some circuit boards that there is a type of black
epoxy that seems to be covering ICs. Is this black epoxy put in place to
hide the IC being used to protect the design or is it a type of cheap
integrated circuit?

Thanks

 

[Danny T]

I've often noticed on some circuit boards that there is a type of black
epoxy that seems to be covering ICs. Is this black epoxy put in place to
hide the IC being used to protect the design or is it a type of cheap
integrated circuit?

I saw the same inside a Dongle issued to stop software copy protection,
it consisted of just a chip with the legs connected to the parallel
pins.. I assumed it was to hide the type of chip, but I don't know for
sure

 

[Michael Bohlender]

Hi there,

I've often noticed on some circuit boards that there is a type of
black epoxy that seems to be covering ICs. Is this black epoxy put in
place to hide the IC being used to protect the design or is it a type
of cheap integrated circuit?

Thanks

most of the time this epoxy is used to replace the IC case!

This technology is known as "Chip on Board" where the silicon chip is glued
directly to the board and then bonded to the PCB connection pads just as
it would be done inside the normal plastic case.

The black cover is put over the chip and its bonding wires after testing
the device for correct function.

Examples for that are:
- LCD displays with integrated controller
- dongles that consist only of one chip
- cheap clocks and watches ...

Bye
Michael

 

[Danny T]

most of the time this epoxy is used to replace the IC case!

This technology is known as "Chip on Board" where the silicon chip is glued
directly to the board and then bonded to the PCB connection pads just as
it would be done inside the normal plastic case.

Is that done because they're cheapskates, or another reason?

 

[peterken]

Is that done because they're cheapskates, or another reason?

yes, it's cheaper
it also takes less space
the epoxy is to protect the chip as well as the bonding wires